INDIANAPOLIS (AP) — School days are being called off for tens of thousands of Indiana students as their teachers make plans for attending a union-organized Statehouse rally.

Some school district officials say so many teachers, including in Michiana, are taking personal time off for the Nov. 19 rally that they wouldn’t be able to find enough substitute teachers to cover classrooms. But they also say they support the push by teachers for a bigger boost in school funding.

The president of the Indiana State Teachers Association says at least 4,000 teachers have registered for the Statehouse lobbying effort on the day legislators are gathering for organization meetings ahead of their 2020 session starting in January.

The union says more than 30 school districts have canceled classes or are having students work online from home that day.